Conventional industrial, commercial and residential architecture commonly involve the use of structural and nonstructural components in the assembly of useful units. Such components are often made from concrete, stone, wood, glass or metal. These materials are well known and are well understood in their applicability to construction purposes.
Wood has been milled into shaped structural components such as sized lumber, trim, post and beam and have also been used to form structural components that can be assembled with glass to form door and window units. Wood, lumber, trim, post, beam and assembled units comprising wood have obvious utility and are well adapted for many uses in many residential or commercial installations. However, the wood used in these applications, under certain circumstances, can have problems. Wood can deteriorate due to the effect of fungus and insect attack. Further, wood members also suffer from cost problems related to the availability of suitable for wood for construction purposes and require substantial upkeep comprising painting or staining. Metal, typically aluminum or steel, components are also often used in industrial, commercial and residential construction. Metal components can suffer from rust or corrosion problems and require their own particular construction skills and maintenance regimen. Vinyl polymeric materials have also been used in formation of structural members and for forming profiles in window and door assembly. Such vinyl materials typically comprise a major proportion of a vinyl polymer with a variety of additive materials that are used. Filled and unfilled (filled with additive materials such as fiber, inorganics, dye etc.) rigid and flexible thermoplastic materials have been extruded or injection molded into a variety of both structural and sealing materials. A thermoplastic polyvinyl chloride has been combined with wood members in the manufacture of PERMASHIELD.RTM. brand windows manufactured by Andersen Corporation for many years. This vinyl cladding technology is disclosed in Zaninni, U.S. Pat. Nos. 2,926,729 and 3,432,885. The technology disclosed in these patents involves the extrusion or injection molding of a thin polyvinyl chloride coating or envelope loosely formed around a shaped wooden structural member.
The polyvinyl chloride thermoplastic materials have also been combined with wood products to make extrusion materials. Initial efforts resulted in a material that can be directly extruded to form a member that has a modulus typically about 500,000 or less. Such members also failed to have adequate compressive strength, coefficient of thermal expansion, coefficient of elasticity, fastener retention or other useful properties required for use in many construction applications.
More recently, U.S. Pat. Nos. 5,486,553, 5,539,027, 5,406,768, 5,497,594, 5,441,801 and 5,518,677, assigned to Andersen Corporation, disclose the use of a thermoplastic such as polyvinyl chloride and wood fiber for the purpose of manufacturing a high strength composite material in the FIBREX.RTM. brand materials technology. Such composites are useful in the manufacture of a structural member such as a hollow profile that can be used in window and door manufacture. These materials have a high modulus (800,000 psi or more) and can be easily manufactured, assembled and installed. These unique high strength materials have had substantial success with respect to their use in window and door manufacture.
The PERMASHIELD.RTM. brand technology and the FIBREX.RTM. brand materials technology have substantial utility and have had substantial success in a variety of applications. Further extensions of thermoplastic polymer technology are useful for other applications. A need exists to obtain materials having enhanced properties.